Political divisions over the welfare system are likely to be highlighted when Labour votes against coalition plans to limit the annual increase in benefits.
The government wants to increase benefits by 1% - less than half the present rate of inflation, which stands at 2.2%.
It says it would be unfair for payments to go up faster than the wages of people in jobs. Labour, which opposes the cap, says it will result in a real-terms cut in support for millions of working people.
Peter Kellner, the president of market research firm YouGov, told Today presenter Evan Davis that while people want governments to be generous, they also want governments that can make the sums work.
He said: "If you have choice between one party that's regarded as mean, but smart, and the other that's nice, but dim, [the public] are likely to go for the mean, but smart party because they think the sums will add up."
Get in touch with Today via
or text us on 84844.